U.S. patent application number 10/394138 was filed with the patent office on 2004-10-14 for method of reducing latency for non-call delivery paging.
Invention is credited to PATEL, TEJASKUMAR, ROSSETTI, DAVID ALBERT.
Application Number | 20040203469 10/394138 |
Document ID | / |
Family ID | 32824919 |
Filed Date | 2004-10-14 |
United States Patent
Application |
20040203469 |
Kind Code |
A1 |
PATEL, TEJASKUMAR ; et
al. |
October 14, 2004 |
Method of reducing latency for non-call delivery paging
Abstract
The paging of mobile stations normally occurs as part of a call
delivery process. As a result, the mobile station needs to refrain
from certain operations such as origination to permit the call
delivery to take place. However, when call delivery is not the
intended consequence of a mobile station page, the method of
reducing latency for non-call delivery paging permits a paged
mobile station or paged party to conduct operations that are
normally prohibited after receiving a page message but before
receiving a release message.
Inventors: |
PATEL, TEJASKUMAR;
(Randolph, NJ) ; ROSSETTI, DAVID ALBERT;
(RANDOLPH, NJ) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. Box 8910
Reston
VA
20195
US
|
Family ID: |
32824919 |
Appl. No.: |
10/394138 |
Filed: |
March 24, 2003 |
Current U.S.
Class: |
455/67.14 ;
455/67.11 |
Current CPC
Class: |
H04W 68/00 20130101 |
Class at
Publication: |
455/067.14 ;
455/067.11 |
International
Class: |
H04B 017/00 |
Claims
I claim:
1. A method of reducing latency in non-call delivery paging of a
mobile station, comprising: performing, at the mobile station, a
prohibited operation without waiting for a release message when a
page message identifiable as an audit-only page message is
received, the prohibited operation being an operation prohibited
from being performed after receipt of the page message paging the
mobile station and before receipt of the release message releasing
the prohibition.
2. The method of claim 1, wherein the page message includes an
identifier indicating the page message is an audit-only page
message.
3. The method of claim 2, wherein the identifier is in a service
option field of the page message.
4. The method of claim 1, wherein the performing a prohibited
operation step sends an origination message.
5. The method of claim 1, further comprising: receiving the
audit-only page message at the mobile station; and sending a page
response in response to the audit-only page message.
6. The method of claim 1, further comprising: receiving a short
data burst (SDB) message; and sending an acknowledgement of the SDB
message.
7. The method of claim 6, wherein the SDB message indicates a
push-to-talk voice-over-IP set-up.
8. A method of reducing latency in non-call delivery paging of a
mobile station, comprising: receiving, at a wireless network, an
origination message from the mobile station without having sent a
release message for a previously sent page message paging the
mobile station.
9. The method of claim 8, prior to the receiving step, further
comprising: sending the page message paging the mobile station.
10. The method of claim 9, wherein the page message includes an
identifier indicating the page message is an audit-only page
message.
11. The method of claim 8, further comprising: receiving a page
response from the mobile station.
12. A method, comprising: receiving, at a mobile station, a wakeup
order; and maintaining an awake state at the mobile station for a
period of time indicated by the wakeup order.
13. The method of claim 12, wherein the wakeup order is an order
message including an identifier indicating the order message is a
wakeup order.
14. The method of claim 12, wherein the identifier is in one of an
order section and an order qualifying section of the order
message.
15. The method of claim 13, wherein the wakeup order includes awake
information in an additional record section of the order message,
the awake information indicating the period of time the mobile
station is to remain in the awake state.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to the paging of mobile
stations, and more particularly, reducing the latency of paging for
non-call delivery. The paging of mobile stations normally occurs as
part of a call delivery process. As a result, the mobile station
needs to refrain from certain operations such as origination to
permit the call delivery to take place. After call delivery occurs,
the mobile station is released and can then perform the prohibited
operations. However, this latency between paging and prohibited
operation also occurs when the object of the page is not call
delivery.
[0002] The set-up of push-to-talk (PTT) voice-over-IP (VoIP)
services involves a non-call delivery paging of a mobile station.
As a result, the latency in the non-call delivery paging causes
latency in the set-up of PTT VoIP service. A better understanding
of this latency and the latency in non-call delivery paging will be
described in detail below in the context of setting up PTT VoIP
communication.
[0003] PTT functionality enables a mobile station to quickly
communicate with one or more other mobile stations substantially
simultaneously, just by, for example, depressing a PTT button on
the calling mobile station. VoIP refers to communication of voice
using digitized voice transported over a packet data network, as
compared to the usual circuit transport method of voice
communication. Accordingly, PTT VoIP service strives to provide PTT
functionality through VoIP communication.
[0004] FIG. 1 illustrates a prior art general architecture for PTT
VoIP communication. As shown, a calling mobile station or calling
party (CgP) 10 communicates with the first wireless network 12 when
initiating a PTT operation. The communication includes information
such as an identifier (e.g., phone number, URL or pin number) of
the party being called (i.e., called party (CdP)) 22. The first
wireless network 12 then communicates with a PTT server 16 over a
public or private, intranet or internet 14 (i.e., an IP network).
The first wireless network 12 provides the PTT server 16 with
information on the CgP 10 and the CdP 22. The first wireless
network 12 manages a database 13 of information regarding the
mobile stations for which the first wireless network 12 provides
wireless communication services. When the first wireless network 12
also provides PTT services, the database 13 also stores, for
example, IP address information in association with the mobile
station's normal identification information.
[0005] The first wireless network 12 communicates a PTT request for
the CgP 10 to the PTT Server 16. The PTT request identifies the CdP
22 and also provides the IP address of the CgP10. Using a database
of information stored therein, the PTT server 16 routes the PTT
request to a second wireless network 20, which in this example
serves the communication needs of mobile stations within a
geographic area that includes the CdP 22. The PTT request is routed
from the PTT server 16 to the second wireless network 20 via a
second public or private, intranet or internet 18 (i.e., an IP
network). As will be appreciated, the first and second wireless
networks 12 and 20 could be the same wireless network when the CdP
22 and the CgP 10 are served by the same wireless network.
Likewise, the first and second public or private, intranet or
internet 14 and 18 could be the same network.
[0006] Using the information, for example, the IP address of the
CdP 22 received from the PTT server 16, the second wireless network
20 identifies the CdP 22 and pages the CdP 22. When the CdP 22
responds to the page and indicates the CdP 22 is available to
receive a PTT VoIP communication, the second wireless network 20
signals the PTT server 16 via the second IP network 18. In turn,
the PTT server 16 signals the first wireless network 12 via the
first network 14. Using the IP address of the CgP 10 in the
signaling from the PTT 16, the first wireless network 12 accesses
the database 13 to identify the CgP 10. The first wireless network
12 then notifies the identified CgP 10 that voice communication can
commence. For example, the notification typically triggers an
audible notification at the mobile station 10 to alert a user that
voice communication can take place.
[0007] The time required to set-up PTT VoIP communication is the
time from when the CgP 10 initiates a PTT operation until the time
when the CgP 10 issues the audible notification. This period of
time is typically referred to as the latency in a PTT VoIP set-up.
A demand currently exists in the industry to reduce this
latency.
[0008] One factor contributing to the latency of PTT VoIP set-up is
establishing the traffic channel to support the PTT VoIP
communication between the second wireless network 20 and the CdP
22. FIG. 2 illustrates a communication flow diagram for
communicating the PTT operation and subsequently establishing a
traffic channel between a second wireless network and called party
as shown in FIG. 1. As shown, to set-up the PTT VoIP communication,
the second wireless network 20 pages the CdP 22. The CdP 22
responds with a page response and enters a page response state if
the page is properly received. When the second wireless network 20
properly receives the page response, the second wireless network 20
sends an acknowledgement (ACK) message to the CdP 22 acknowledging
receipt of the page response.
[0009] Next, the second wireless network 20 sends a short data
burst (SDB) message to the CdP 22 notifying the CdP 22 that the CdP
22 is being called for PTT VoIP communication. A SDB message is an
IP packet sent between a mobile and a wireless network without a
traffic channel assigned to this task; namely, the IP packet is
sent over common or shared channels. When the CdP 22 properly
receives the SDB message, the CdP 22 sends an ACK message
acknowledging receipt of the SDB message. The second wireless
network 20, in turn, sends an ACK message acknowledging receipt of
the ACK message from the CdP 22. The second wireless network 20
will then send a release message to the CdP 22. The release message
indicates that the CdP 22 is released from the page (i.e., is
released from the page response state), and can now perform other
operations such as an origination. Accordingly, FIG. 2 demonstrates
the latency in this non-call delivery paging. Because the SDB
message notified the CdP 22 of intended PTT VoIP communication, the
CdP 22 sends an origination message once the release message has
been received. The origination message requests that the second
wireless network 20 establish a traffic channel between the CdP 22
and the second wireless network 20 to support the PTT VoIP
communication. This portion of FIG. 2 further demonstrates the
impact the latency in non-call delivery paging has on the latency
in PTT VoIP set-up.
SUMMARY OF THE INVENTION
[0010] The paging of mobile stations normally occurs as part of a
call delivery process. As a result, the mobile station needs to
refrain from certain operations such as origination to permit the
call delivery to take place.
[0011] However, when call delivery is not the intended consequence
of a mobile station page, the present invention provides for
reduced latency in non-call delivery paging. The present invention
provides a method of reducing latency in non-call delivery paging
by permitting a paged mobile station or paged party to conduct
operations that are normally prohibited after receiving a page
message but before receiving a release message.
[0012] According to one exemplary embodiment, a page message sent
by a wireless network includes an identifier identifying the page
message as an audit-only page message. Based on the recognition of
this identifier, the paged mobile station can conduct operations
such as origination without waiting for a release from the page
response state.
[0013] According to another exemplary embodiment, an order message
sent by a wireless network includes an identifier identifying the
order message as a wakeup order. The wakeup order is similar to the
audit-only page in that it may be used as a locate function for
non-call delivery. Based on the recognition of the wakeup order,
the paged mobile station sends an acknowledgement, and can conduct
operations such as origination. Because a mobile station does not
require a release message with respect to an order message, the
mobile station conducts, for example, origination without waiting
for a release message.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The present invention will become more fully understood from
the detailed description given herein below and the accompanying
drawings, wherein like elements are represented by like reference
numerals, which are given by way of illustration only and thus are
not limiting of the present invention and wherein:
[0015] FIG. 1 illustrates a prior art general architecture for PTT
VoIP communication;
[0016] FIG. 2 illustrates a communication flow diagram for
communicating the PTT operation and subsequently establishing a
traffic channel between a second wireless network and called party
as shown in FIG. 1;
[0017] FIG. 3 illustrates a well-known format of a page
message;
[0018] FIG. 4 illustrates a well-known format of an order message;
and
[0019] FIG. 5 illustrates a communication flow diagram for
communicating the PTT operation and establishing a traffic channel
between a second wireless network and called party according to one
embodiment of the present invention.
DETAILED DESCRIPTION OF EMBODIMENTS
[0020] For a proper understanding of the present invention, the
well-known format for a page message will be described, and then a
well-known format for an order message will be described. The
embodiments of the present invention are then described, and an
exemplary operation of the present invention using the architecture
of FIG. 1 is described. However, it should be understood that the
present invention is not limited in application to this
architecture.
[0021] Page Message Format
[0022] FIG. 3 illustrates a well-known format of a general page
message according to TIA/EIA IS-2000. A general page message may
include several pages or page records packaged together as a single
message. As shown, the general page message includes a general page
information section, a number of pages, a reserved section and an
error correction (CRC) section. The general page information
section includes general message information-for example, message
number, length of message, etc. Each individual page has the format
as illustrated in detail for the first page. This format will be
discussed in detail below. The reserved section is a portion of the
of the general page message reserved for future use. The CRC
section includes the error correction code information for the
general page message.
[0023] As shown, each page record includes a page class field, a
mobile station (MS) identification field and a service option field
as well as other fields not pertinent to this disclosure. The page
class field indicates the class of mobile station identifier used
in this page record. For example, classes of mobile station
identifier include Broadcast, international mobile station
identifier (IMSI), temporary mobile station identifier (TMSI), etc.
The mobile station identification field identifies the paged mobile
station using the class of mobile station identifier given in the
page class field. The service option field indicates the type of
service for which the mobile station is being paged (e.g. voice
call delivery, short text message delivery, IP Packet Data,
etc.)
[0024] Order Message Format
[0025] FIG. 4 illustrates a well-known format of an order message
according to TIA/EIA IS-2000. As shown, the order message includes
a general message information section, an address section, an order
section, an order qualifying section, an additional record section
and a CRC section as well as other sections not pertinent to this
disclosure. The general message information section includes
general message information--for example, message number, length of
message, etc. The address section identifies, for example, the
mobile station or mobile stations to which the order is directed.
The order section indicates the type of order. The order qualifying
section is an additional section for identifying the type of order.
Namely, together the order section and order qualifying section
uniquely define a type of order-for example, an acknowledgement
(ACK) message, a retry order, a periodic pilot measurement order,
etc. The additional record section provides additional
order-specific information, if necessary (e.g., time to wait before
retry or the periodicity of performing pilot measurements.). The
CRC section includes the error correction code information for the
order message.
[0026] A First Embodiment
[0027] In a first embodiment of the present invention, the second
wireless network 20 generates a page message for the CdP 22 having
the format as illustrated in FIG. 3. However, the second wireless
network 20 adds a special code in the service option field to
indicate that the page message is an audit-only page message. Upon
receipt of a page message identified as an audit-only page message,
the CdP 22 will not prohibit operations normally prohibited until
receipt of a release message. Accordingly, as will be described in
detail below with respect to FIG. 5, the CdP 22 can proceed with,
for example, sending an origination message even though a release
message has not been received from the second wireless network 20.
Other prohibited operations that can be performed include sending a
short text message via short message service, etc.
[0028] FIG. 5 illustrates an exemplary operation of the present
invention. More specifically, FIG. 5 illustrates a communication
flow diagram for communicating the PTT VoIP operation and
establishing a traffic channel between the second wireless network
20 and the CdP 22 for PTT VoIP communication. As shown, to set-up
the PTT VoIP communication, the second wireless network 20 pages
the CdP 22. The second wireless network 20 pages the CdP 22 using
an audit-only page message as discussed in detail above. The CdP 22
responds with a page response if the audit-only page message is
properly received. When the second wireless network 20 properly
receives the page response, the second wireless network 20 sends an
acknowledgement (ACK) message to the CdP 22 acknowledging receipt
of the page response.
[0029] Next, the second wireless network 20 sends a short data
burst (SDB) message to the CdP 22 notifying the CdP 22 that the CdP
22 is being called for PTT VoIP communication. When the CdP 22
properly receives the SDB message, the CdP 22 sends an ACK message
acknowledging receipt of the SDB message. The second wireless
network 20, in turn, sends an ACK message acknowledging receipt of
the ACK message from the CdP 22.
[0030] Because the SDB message notified the CdP 22 of intended PTT
VoIP communication, the CdP 22 sends an origination message to the
second wireless network 20. The origination message requests that
the second wireless network 20 establish a traffic channel between
the CdP 22 and the second wireless network 20 to support the PTT
VoIP communication. As shown, because the CdP 22 identifies the
page message sent from the second wireless network 20 as an
audit-only page message, the CdP 22 does not wait for a release
message before sending the origination message. As such, the
latency with respect to non-call delivery paging is reduced, and in
this exemplary operation, latency in, PTT VoIP set-up is thus
reduced.
[0031] A Second Embodiment
[0032] In a second embodiment of the present invention, the second
wireless network 20 generates an order message for the CdP 22
having the format as illustrated in FIG. 4. However, the second
wireless network 20 uses a special code in the order field or the
order qualifying field to indicate that the order message is a
wakeup order. The CdP 22 recognizing the order message as a wakeup
order directed to itself, sends an acknowledgement response.
Because the wakeup order is not a page, the mobile station remains
capable of initiating other services such as origination.
[0033] With respect to FIG. 5 discussed above, according to this
embodiment of the present invention, the second wireless network 20
would send the wakeup order message to the CdP 22 instead of the
audit-only page message and would receive an acknowledgement
response as opposed to a page response. Otherwise, the operation
shown in FIG. 5 is the same for this embodiment. Accordingly, the
CdP 22 can proceed with, for example, sending an origination
message even though a release message has not been received from
the second wireless network 20.
[0034] Furthermore, as is well-known, mobile stations operate in a
slotted and non-slotted mode. In the slotted mode, the mobile
station operates in a powered down or sleep state to save battery
life and only awakes (e.g., powers up) to monitor a shared or
common channel periodically. In the non-slotted mode, the mobile
station is continually in the awake state. Typically, when a mobile
station receives a page message, the mobile station, if in the
slotted mode, will move to the non-slotted mode for a fixed period
of time (e.g., 12 seconds). In one version of this embodiment of
the present invention, a slotted mobile station operates in the
same manner when a wakeup order is received.
[0035] In another version of this embodiment, the wakeup order
according to the present invention provides the added flexibility
of being able to specify the period of time a slotted mobile
station remains in the awake state in response to the wakeup order.
Specifically, according to this further aspect of the second
embodiment, the second wireless network 20 places data in the
additional record field indicating the period of time the mobile
station is to remain in the awake state in response to the wakeup
order.
[0036] It will further be appreciated that the wakeup order could
also be used to keep a mobile station, like the CdP 22, awake after
receipt of an SDB message and until another SDB message could be
delivered. In this case, the wireless network would know that the
mobile was awake and could send messages immediately.
[0037] The invention being thus described, it will be obvious that
the same may be varied in many ways. Such variations are not to be
regarded as a departure from the spirit and scope of the invention,
and all such modifications as would be obvious to one skilled in
the art are intended to be included within the scope of the present
invention.
* * * * *